Provision of urea–molasses blocks to improve smallholder cattle weight gain during the late dry season in tropical developing countries: studies from Lao PDR

Context Large-ruminant production in developing countries is inefficient with low growth rates and declining weights, particularly in the dry season. Aims The impact of ad libitum supplementation of cattle with high-quality molasses blocks (20 kg) containing either 8% urea (UMB) or nil urea (MB), was examined. Methods Field trials on smallholder farms compared weight changes and average daily gains (ADG = g/day) data of young calves <8 months of age (n = 25); growing calves 8–24 months (n = 35) and lactating cows (n = 46), of the indigenous breed when accessing either UMB or MB, with data being collected at Weeks 1, 4, 8 and 12. A pen study was also conducted at a research station involving mature, lactating crossbred cows (n = 37). Surveys of farming families experiencing use of the blocks was conducted (n = 20). Key results On smallholder farms, animals accessing UMBs were heavier than those accessing MBs at every collection day and in young calves these differences were statistically significant (P < 0.05). ADGs were higher in cattle accessing UMB than in those accessing MBs. Young calves had the highest ADG (251–265 g/day), followed by growing calves (198–237 g/day) and lactating cows (187–190 g/day), although differences in ADG between UMB and MB cohorts were not considered significant (young calves P = 0.562; growing calves P = 0.509; and lactating cows P = 0.993). Results from the pen study identified that ADGs were not significantly different (P = 0.933) between crossbred cows accessing MBs (236 g/day) and cows accessing UMBs (229 g/day). Surveys of farmers using blocks confirmed that their animals were calmer and healthier, and had better coat condition with minimal external parasites; these farmers wished to purchase the blocks and were willing to pay a mean up to US$6.5 ± 2.3 per block. Conclusions Provision of UMBs and MBs in Laos in the late dry season improved cattle growth rates, which is consistent with previous studies and far superior to the base-line data from Laos demonstrating declining ADGs. Farmers considered that the blocks contributed greatly to herd management and improved sale-ability of their cattle. Implications Provision of molasses blocks on low-input smallholder farms in developing countries significantly improves production efficiency, offering an ‘entry point’ intervention while forages are becoming established.

Can fenbendazole-medicated molasses blocks control Toxocara vitulorum in smallholder cattle and buffalo calves in developing countries? Studies from upland Lao PDR

Context Anthelmintic treatments are not widely adopted by smallholder farmers in Laos (Lao People’s Democratic Republic) to treat bovid Toxocara vitulorum, resulting in high calf morbidity and mortality. Aims Field trials were conducted to provide baseline efficacy data on an alternative, easy-to-use treatment by provision of fenbendazole-medicated molasses blocks (FMB) in situ. Methods Participating villages were randomly allocated to the following treatments: (1) conventional orally administered pyrantel, (2) access to FMB, (3) access to non-medicated molasses blocks (MB), and (4) no blocks (control). Faecal eggs per gram (EPG) and weight were monitored in cattle (n = 171) and buffalo calves (n = 44) under field conditions for 48–56 days. Key results In 2016, the MB treatment was associated with the fastest reduction in predicted average EPG at 2% per day, while FMB and pyrantel had an equivalent reduction of 1% per day, relative to the control (P = 0.062). Predicted average weight also differed significantly among treatments, with pyrantel and MB having the greatest average daily gain at 230 g and FMB at 200 g, which was higher than for control calves at 170 g (P = 0.002). In buffalo calves, treatment was not significantly associated with EPG or weight. The 2018 trial corroborated that FMB and MB treatments were associated with increased EPG reductions in cattle at 3% per day, relative to control calves (P = 0.007). Again, the MB treatment had the greatest predicted average daily gain at 200 g, compared with FMB calves at 160 g and control calves at 150 g (P = 0.005). Conclusions The field trials provided baseline evidence that FMB and MB have potential applications in reducing environmental contamination of T. vitulorum eggs and may improve calf growth in low-input systems. However, further testing ex situ is required to control for variability in calf weight and T. vitulorum burdens, so as to optimise anthelmintic doses, assess the addition of urea to the block formula and assess product marketability. Implications If successful, medicated nutrient blocks may be a simple method to reduce calf mortality and morbidity, enhancing the reproductive efficiency of large ruminant production in smallholder farms in developing countries.

Do triclabendazole medicated molasses blocks have a role in control of Fasciola gigantica in smallholder cattle production in Lao PDR?

Smallholder cattle production in many developing tropical countries including Laos is compromised by widespread endoparasitism, with limited farmer knowledge of parasites and facilities for administration of therapeutics. We report a pilot study examining the potential for triclabendazole provided in medicated molasses blocks offered to control Fasciola gigantica in smallholder cattle production. This study involved 241 cattle allocated into three groups: (1) triclabendazole (as Fasinex®, Novartis Animal Health Australia, Pty Ltd) medicated molasses blocks (MMB) with each tonne of MMB containing 0.5 kg triclabendazole; (2) unmedicated molasses blocks; and (3) a Control group. Data and faecal samples were obtained at Weeks 1, 4, 8 and 12 for faecal egg counts (FEC) determination. Reductions in FEC in the MMB group of 90.48% and a mean FEC of 4 ± 17 eggs per gram of faeces at 12 weeks post-treatment was observed, with liveweight increasing from 174.60 (±3.35) kg to 191.50 (±3.69) kg in Weeks 1 and 12, respectively (P = 001) and an average daily weight gain of 201 g/day. Reduction in FEC in the unmedicated molasses blocks group was also observed, by 28.78% and 18.96%, with liveweight increasing from 179.50 (±3.35) kg to 189.90 (±6.05) kg in Weeks 1 and 12 respectively (P = 0.3), with an average daily gain of 124 g/day. This study suggests that productivity was enhanced when triclabendazole was added to the blocks, delivering parasite suppression or potentially therapeutic doses on ad libitum feeding of the MMB. Although further work is required to establish the therapeutic potential of MMB, the use of MMB may offer a parasite management and nutritional supplementation strategy for smallholder farmers, particularly in Laos and other countries where unmanaged Fasciola spp. infestations reduce ruminant productivity and facilities for animal restraint to enable delivery of oral anthelmintics, are largely non-existent.

Abattoir surveillance of Sarcocystis spp., Cysticercosis ovis and Echinococcus granulosus in Tasmanian slaughter sheep, 2007-2013

OBJECTIVE

To estimate the prevalence of macroscopic Sarcocystis spp., Cysticercus ovis and Echinococcus granulosus recorded at routine postmortem inspection of Tasmanian slaughter sheep during 2007 to 2013.

METHODS

A retrospective analysis of routine postmortem meat inspection data maintained on 352,325 Tasmanian adult slaughter sheep inspected across nine abattoirs in Tasmania, Victoria and South Australia as part of the National Sheep Health Monitoring Project (NSHMP).

RESULTS

During the period 1 September 2007 to 30 June 2013, the estimated prevalence of macroscopic Sarcocystis spp. was 14.3%, C. ovis was 3.2% and E. granulosus was 0.01%. Mean Sarcocystis spp. line prevalence ranged from 0% to 33.5%. Significant between-abattoir differences in the level of sarcosporidiosis (P < 0.001) and C. ovis were found (P < 0.001). Overall, very low levels of hydatidosis were recorded throughout the surveillance period. Predicted within-line prevalence of macroscopic sarcocysts in animals coming from a known/recorded local government area (LGA) (P < 0.001) was lower than that of lines where the LGA was unknown or not recorded. A higher prevalence of sarcocystosis was recorded in lines of sheep aged ≥ 2 years compared with those < 2 years (P < 0.001).

CONCLUSION

Reasons for the significant between-abattoir differences in recorded levels of ovine sarcosporidiosis and cysticercosis remain unknown, but may represent sampling bias, with subsets of slaughter sheep going to abattoirs with different tiers or access to markets. Further investigation into apparent differences, including epidemiological studies of properties with high lesion prevalence, comparing meat inspector diagnostic sensitivity, assessing the effect of line speed and tiers and market access in different abattoirs, may be useful.

Socioeconomic impact of forage-technology adoption by smallholder cattle farmers in Cambodia

In Cambodia, adoption of forage technology is recommended to smallholder cattle farmers as an alternative to the widespread practice of feeding nutritionally inferior rice straw and collected or grazed native grasses. Although field research has demonstrated the nutritional benefits to cattle of smallholders adopting forage technology in Cambodia, we extended these studies by investigating the impacts and financial metrics of forage technology adoption in January 2011 by 120 smallholder participants from the ‘Best practice health and husbandry of cattle Cambodia’ (AH/2005/086) project. Farmers were classified by intervention level (high (HI) or low (LI) intervention) and forage technology adoption (adopter HI, non-adopter HI and non-adopter LI). Information on cattle-feeding practices, including household labour demands of sourcing feed for cattle, plus input costs of forage-plot establishment by adopter HI farmers, was collected and analysed. Results were that while the establishment of forages did not have a significant effect on the use of traditional feed sources such as rice straw, crop bi-products and crop residues, grazing of cattle on native pastures was less common among adopter households. Adopter households also reported a significant (P < 0.05) reduction in daily time spent sourcing feed and reduced involvement of women and children in sourcing feed for cattle compared with non-adopter households. Average total cost of inputs to forage-plot establishment per 100 m2 ranged from US$1.40 to US$16.88, with an average cost of US$5.60. Seed costs were estimated at US$0.50 per 100 m2 for a total input cost of US$6.10 per 100 m2. Partial budget analysis was used to compare the value of forage feeding of the following two scenarios over a 6-month wet-season period: (1) forage-plot establishment and forage feeding across the herd; and (2) forage-plot establishment and target feeding (fattening) of one animal. A net profit of US$139.01 was indicated for Scenario 1 and US$152.94 for Scenario 2 and Monte Carlo simulation indicated similar financial outcomes for both scenarios, namely US$169.09 (95% CI: –17.00, 402.00) and US$172.33 (95% CI: 66.80, 305.80) respectively. We conclude that the reduced labour burden on women and children plus the potential increased household income from forage establishment and forage feeding, support recommendations of forage technology as a strategy to improve the livelihoods of smallholder cattle farmers in Cambodia.

Investigation of smallholder farmer biosecurity and implications for sustainable foot-and-mouth disease control in Cambodia

In Cambodia, the majority of the population is rural and reliant on subsistence agriculture, with cattle raised by smallholder farmers using traditional practices, resulting in low productivity and vulnerability to foot-and-mouth disease (FMD). As FMD causes deleterious impacts on rural livelihoods, known FMD risk factors were reviewed, using knowledge, attitudes and practice (KAP) surveys of smallholders (n = 240) from four regions. The study aimed to understand current biosecurity threats to smallholder livelihoods and investigate the hypothesis that smallholder farmers practising FMD risk management should be associated with higher incomes from cattle. Descriptive data were examined to demonstrate trends in KAP and a multivariable linear regression model developed to identify cattle income predictors. Results showed that baseline mean knowledge scores were low at 28.4% across all regions and basic biosecurity practices, including quarantine of new cattle, isolation of sick cattle and FMD vaccination, were lacking. As farmers purchase and sell cattle from and to various administration levels (including export), there is high risk of FMD transmission into and from smallholder communities. The final multivariable linear regression model identified significant explanatory parameters for annual cattle income, including region, number of calves born, forage plot size (ha), vaccination of cattle and the number of cattle purchased (F pr. < 0.001, R²  = 29.9). Individual biosecurity practices including FMD vaccination were not significant predictors of income. With the current focus of farmers on treatment of FMD with inappropriate antibiotics leading to potential anti-microbial residue issues, yet receptivity to payment for vaccine in most regions, there is an urgent need for a coordinated national biosecurity and FMD management public awareness campaign. Further, to enhance the association between improved cattle health and rural livelihoods, it is recommended that livestock development programmes implement a systems approach to enhance farmer KAP in biosecurity, nutrition, reproduction and marketing of cattle.

Fasciola gigantica infection in large ruminants in northern Laos: smallholder knowledge and practices

High prevalence of Fasciola spp. infection in smallholder large ruminant farming systems has been confirmed in many regions of South-East Asia, yet information on trematode knowledge and any control practices of large ruminant farmers is lacking. We surveyed smallholder farmers (n = 326) in northern Laos on knowledge of liver fluke and its management in their large ruminants, identifying 93.1% of farmers had no knowledge and 6.9% minimal knowledge of the parasite and impacts on large ruminant production. The survey further confirmed anecdotal reports that control or prevention measures were lacking, with none of the surveyed producers using effective anthelminthic treatments or grazing strategies to control Fasciola spp. This was despite 20.6% of farmers having reported observing leaf-shaped parasites in the liver of their cattle or buffalo when slaughtered in the past. With increasing demand for red meat in the region, subsistence smallholder farmers are able to supply this market and increase their income. Athough the production impact of fascioliasis in large ruminants in these farming systems still needs to be quantified, farmer knowledge and control of fascioliasis in this region is likely to increase livestock productivity and improve rural livelihoods. This would help to address regional rural poverty and food insecurity, but requires improved knowledge to address the identified knowledge and practice gaps on presence, impact and control of fasciolosis. The majority (95.4%) of surveyed farmers indicated a desire to learn more about fascioliasis in large ruminants, suggesting that extension methods used in the past need adapting to result in more effective knowledge transfer and changed practices in future.

Smallholder large ruminant health and production in Lao PDR: challenges and opportunities for improving domestic and regional beef supply

Indigenous yellow cattle (Bos indicus) and Asiatic swamp buffalo (Bubalus bubalis) are important livestock species in the Lao People’s Democratic Republic (Laos). Data from 2011 estimated there was a national herd of 1 586 200 cattle and 774 200 buffalo, with average numbers of 5.3 cattle and 3.4 buffalo per farm household, indicating that the majority of farm households with large ruminants were smallholders, retaining large ruminants as a storage of wealth, for sale as meat, and as a source of manure fertiliser. Increasing demand for red meat in both domestic and neighbouring markets, driven by rapidly growing economies and urbanisation, offers opportunities for Lao smallholders to gain more income from their livestock. However, improving cattle and buffalo production and a more sustainable supply of safe beef and buffalo meat, requires that numerous production, health and welfare constraints be addressed, including: prevalence of important infectious and parasitic diseases, nutritional deficits particularly in the dry season, undeveloped trading, meat processing and marketing systems, limited veterinary and extension service capacity, adverse impacts from climate change and cultural practices specific to buffalo husbandry, plus policy developments that recognise and adapt to changes in land use. Improvements in large ruminant health, processing and marketing are of particular importance as these will enable poor smallholder farmers to participate in emerging beef markets and expand other agricultural enterprises, improving rural livelihoods, with potential reductions in rural poverty and increased food security. This paper identifies the strategic interventions that may increase the supply of cattle and buffalo and improve rural livelihoods in Laos and the Greater Mekong Subregion.

Challenges for beef production in smallholder communities with low reproductive management skills: a case study from Northern Lao PDR

Improved large ruminant productivity is increasingly acknowledged as a pathway for the alleviation of rural poverty and food insecurity in smallholder communities in Southeast Asia; yet, in much of Laos, bovine reproductive management is practically absent. Large ruminant reproduction skills were studied, using face-to-face surveys (n=60) of the knowledge, attitudes, and practices (KAP) of farmers, plus an extension of an examination of parameters of reproductive efficiency (n = 1786 cattle and 434 buffalo) in the northern provinces of Luang Prabang and Xieng Khouang. The surveys particularly involved female farmers to provide gender-disaggregated data, with females making up 38.3 % of participants. Results confirmed that KAPs of smallholder farmers on bovine reproductive management were low (34-46 %) with trends toward higher KAP scores in male survey respondents. Poor reproductive parameters were identified in both provinces, with low calving percentages of 54-75 and 45-54 % in cattle and buffalo groups, respectively, and prolonged inter-calving intervals of 14.1-19.8 and 26.0 months for the cattle and buffalo groups, respectively. Improving the reproductive efficiency of large ruminants in the northern upland regions would enable smallholder farmers to be more effectively engaged in the dramatic economic growth of the Southeast Asia region, although these findings indicate that intensive training and supportive interventions are required to improve large ruminant reproductive outcomes in communities that have low-level large ruminant husbandry skills.

Effectiveness of Gudair™ vaccine for the control of ovine Johne's disease in flocks vaccinating for at least 5 years

OBJECTIVE

Examine the prevalence of shedding of Mycobacterium avium subsp. paratuberculosis (Mptb) at least 5 years after starting vaccination with Gudair™ in flocks of varying initial prevalence of ovine Johne's disease (OJD) and identify risk factors for variation in vaccine efficacy.

METHODS

Pooled faecal culture (PFC) was conducted for 41 flocks from southern NSW and Victoria to determine estimates of current OJD prevalence. The data were compared to estimates of prevalence at or prior to commencement of vaccination at least 5 years earlier, based on available serological or PFC tests when vaccination commenced. A cross-sectional study was conducted to identify risk factors for differing prevalence levels in 36 of the flocks.

RESULTS

Historical data enabled classification of 37 flocks as high (13; 35.1%), medium (10; 27.0%) or low (14; 37.8%) estimated initial OJD prevalence. Results of PFC in 2008-09 identified that 81.1% (30/37) of flocks had detectable shedders, with 48.6% (18/37) flocks still classified as medium or high OJD prevalence, including 50% (7/14) of flocks initially classified as low prevalence. Shedding was not detected in 18.9% (7/37) flocks. Flocks with OJD prevalence exceeding 1% at 5 years or more following the commencement of vaccination were associated with reports of sheep straying and introduction of new sheep.

CONCLUSION

Despite significant declines in estimated OJD prevalence following vaccination for ≥5 years, 81.1% of flocks were shedding Mptb and considered at risk of spreading the disease or suffering recrudescence of losses if vaccination were to cease. Flock managers are advised to persist with vaccination.

Paratuberculosis in sheep and goats

Paratuberculosis is a chronic insidious, often serious, disease of the global small ruminant industries, mainly causing losses from mortalities and reduced productivity on-farm, interference in trading and, in Australia, profound socio-economic impacts that have periodically compromised harmony of rural communities. The pathogenesis, diagnosis, impacts and disease management options for ovine and caprine paratuberculosis are reviewed, comparing current controls in the extensive management system for sheep in wool flocks in Australia with the semi-intensive system of dairy flocks/herds in Greece. Improved understanding of the immune and cellular profiles of sheep with varying paratuberculosis outcomes and the recognition of the need for prolonged vaccination and biosecurity is considered of relevance to future control strategies. Paratuberculosis in goats is also of global distribution although the prevalence, economic impact and strategic control options are less well recognized, possibly due to the relatively meagre resources available for goat industry research. Although there have been some recent advances, more work is required on developing control strategies for goats, particularly in dairy situations where there is an important need for validation of improved diagnostic assays and the recognition of the potential impacts for vaccination. For all species, a research priority remains the identification of tests that can detect latent and subclinical infections to enhance removal of future sources of infectious material from flocks/herds and the food chain, plus predict the likely outcomes of animals exposed to the organism at an early age. Improving national paratuberculosis control programs should also be a priority to manage disease risk from trade. The importance of strong leadership and communication, building trust within rural communities confused by the difficulties in managing this insidious disease, reflects the importance of change management considerations for animal health authorities. Although concerns of vaccine efficacy, safety and issues with diagnosis and administration persist, vaccination is increasingly recognized as providing a robust strategy for managing paratuberculosis, having made important contributions to the health of Australian sheep and the lives of producers with affected properties, and offering a mechanism to reduce risk of infection entering the food chain in ovine and caprine products.

Progressing smallholder large-ruminant productivity to reduce rural poverty and address food security in upland northern Lao PDR

Applied participatory research on large-ruminant health and production was conducted in six villages in northern Lao PDR. Three villages were classified as ‘high intervention’ (HI) and the remaining three as ‘low intervention’ (LI) sites, with a suite of health and productivity interventions implemented in the HI sites enabling comparison of outcomes with the LI sites, where only a vaccination program was introduced. A 3-year longitudinal study to establish baseline production variables, including liveweight, average daily weight gain (ADG) and reproductive performance, was conducted. The study involved 1500 head of cattle and buffalo that were ear-tagged and weighed every 3–4 months between 2008 and 2011, producing 10 data-collection points. Significant differences in ADG of the cattle between the provinces (P < 0.001), but not between HI and LI villages (P = 0.39), was observed. Low calving rates (51–75% and 41–52%) and inter-calving intervals (13.6–15.7 and 18.6–20.6 months) for cattle and buffalo, respectively, were observed. An on-farm large ruminant-fattening trial (n = 44) was conducted over a 4-month period to examine differences in productivity between cut-and-carry stall fattening (n = 26) and free-grazing (n = 18) systems. Cattle and buffalo in fattening stalls (320 and 217 g/day) had significantly greater ADG than those free-grazing (40 and 85 g/day) (P < 0.001 and P = 0.001). The increase in sale value for fattened cattle and buffalo was US$78 and US$123, respectively. The longitudinal study indicated that if risks of important diseases such as foot and mouth disease and haemorrhagic septicaemia are controlled by vaccination and biosecurity, improved productivity outcomes in northern Lao PDR can be achieved by establishing forage plantations to better manage variations in seasonal availability of feed and enabling fattening. We conclude that improved large-ruminant productivity, by improving health and nutrition practices, offers opportunities for smallholder farmers to increase livestock income, alleviate rural poverty and improve regional food security in South-east Asia.

Target feeding for improved smallholder beef production in the Mekong region: lessons from Cambodia and Lao PDR

Increased demand for red meat throughout the Greater Mekong Subregion (GMS) presents smallholder cattle and buffalo farmers with an opportunity to supply better quality animals to expanding regional markets. Cattle were target-fed in Cambodia with introduced forages to achieve gains of 0.19 kg/day over a 104-day period and this practice was compared with traditional cut-and-carry feeding practices where animals lost on average 0.04 kg/day. Target-fed animals were predicted to gain, on average, 25.9 kg more weight than animals fed in a traditional manner (P = 0.057), and to improve their estimated value by more than US$60. These outcomes were similar to outcomes in Lao PDR, where cattle and buffalo in fattening stalls gained 0.32 and 0.22 kg/day, respectively, over a 4-month period, and 0.04 and 0.09 kg/day when free-grazing. Greater weight gains are possible if farmers feed forages at the recommended 15% of bodyweight on a fresh-weight basis per day. Lack of knowledge of animal weights by farmers and traders was addressed by the creation of an accurate weight tape to provide a cheap and easy tool to monitor animal production and health, and to assist in negotiating a fair sale value. However, increased knowledge of appropriate forage plot size and feeding requirements of animals to be target-fed is required for farmers to change from being livestock keepers to livestock producers. To increase supply for the growing demand for red meat, an ongoing, multi-disciplinary extension program should be a priority for livestock improvement programs in the GMS.

The impact of best practice health and husbandry interventions on smallholder cattle productivity in southern Cambodia

Future food security has become a major global concern and is particularly important in the Greater Mekong Subregion where several countries have seen rapid urban economic development and increasing demand for red meat. In Cambodia, the majority of livestock producers are subsistence or semi-subsistence rural smallholder farmers using cattle as a source of protein, fertiliser, draught power, and asset storage. Potential income from smallholder cattle is limited by a range of factors that compromise productivity, including endemic diseases, poor nutrition, and lack of knowledge of husbandry techniques and marketing practices. To address the developing opportunities to improve rural incomes from cattle production in Cambodia, a 4-year longitudinal study was conducted to examine ‘best practice’ interventions that could improve productivity and profitability of cattle within smallholder farming systems. The study involved six villages from three provinces, with two villages in each of the provinces of Takeo, Kandal and Kampong Cham paired and designated as either high intervention (HI) or low intervention (LI). A best practice intervention program was introduced to the HI villages to develop the husbandry skills of farmers, including implementation of forage technology, disease prevention through vaccination for foot-and-mouth disease and haemorrhagic septicaemia, deworming, and education in nutrition, biosecurity, disease control, and marketing. Between April 2008 and February 2012, eight repeat-measures capturing data on animal health and production, including cattle weights used to evaluate the impact of interventions on average daily gains, were completed. Cattle in HI villages had significantly (P < 0.01) higher mean liveweight during the last three sampling periods, and average daily gains were 2.4 times higher than in cattle of the LI villages. This study provides evidence that best practice interventions resulted in improved cattle productivity, farmer knowledge and positive impacts on household income over time, offering a pathway that can address food security concerns and more rapidly alleviate rural poverty in the GMS.

Forage growing as an incentive to improve smallholder beef production in Cambodia

A major challenge for large ruminant improvement projects in developing countries is smallholder farmer engagement that promotes the value of knowledge in informed decision making. Most large ruminant smallholder farmers in Cambodia are considered to be livestock keepers and will become livestock producers only if they recognise the production and financial benefits from improved health and management practices. The benefits of growing and feeding five introduced forage species was investigated as a potential entry point for smallholder farmer engagement in southern Cambodia. The mean chemical composition, digestibility and estimated metabolisable energy (ME; MJ/kg DM) of introduced forages at 30 days after first harvest were comparable to published values. An initial establishment of 52 fodder plots covering 2.6 ha in 2008 expanded to 1306 plots covering 45 ha, including non-project farmers from surrounding areas. The establishment of forage plots in high-intervention project villages provided an improvement in average daily liveweight gain of cattle and saved farmers up to 2 h labour per day. This strategy provided a platform for increased uptake and adoption of livestock health and production interventions.

Improving Smallholder Farmer Biosecurity in the Mekong Region Through Change Management

Transboundary animal diseases including foot-and-mouth disease and haemorrhagic septicaemia remain a major constraint for improving smallholder large ruminant productivity in the Mekong region, producing negative impacts on rural livelihoods and compromising efforts to reduce poverty and food insecurity. The traditional husbandry practices of smallholders largely exclude preventive health measures, increasing risks of disease transmission. Although significant efforts have been made to understand the social aspects of change development in agricultural production, attention to improving the adoption of biosecurity has been limited. This study reviews smallholder biosecurity risk factors identified in the peer-reviewed literature and from field research observations conducted in Cambodia and Laos during 2006-2013, considering these in the context of a change management perspective aimed at improving adoption of biosecurity measures. Motivation for change, resistance to change, knowledge management, cultural dimensions, systems theory and leadership are discussed. Due to geographical, physical and resource variability, the implementation of biosecurity interventions suitable for smallholders is not a 'one size fits all'. Smallholders should be educated in biosecurity principles and empowered to make personal decisions rather than adopt prescribed pre-defined interventions. Biosecurity interventions should be aligned with smallholder farmer motivations, preferably offering clear short-term risk management benefits that elicit interest from smallholders. Linking biosecurity and disease control with improved livestock productivity provides opportunities for sustainable improvements in livelihoods. Participatory research and extension that improves farmer knowledge and practices offers a pathway to elicit sustainable broad-scale social change. However, examples of successes need to be communicated both at the 'evidence-based level' to influence regional policy development and at the village or commune level, with 'champion farmers' and 'cross-visits' used to lead local change. The adoption of applied change management principles to improving regional biosecurity may assist current efforts to control and eradicate transboundary diseases in the Mekong region.

Topical anesthesia mitigates the pain of castration in beef calves

Castration involves the removal of the testes and is performed to improve product quality and management of male calves. The procedure has been proven to cause significant pain and stress, and despite several attempts to reduce the impact of castration on animal welfare, there has yet to be a practical and affordable option made available for farmer application. To address this issue, we conducted 2 trials (n = 18 and 27) to examine the efficacy of topical anesthetic Tri-Solfen (TA) to alleviate the pain of surgical castration. Angus bull calves (135.8 ± 5.7 kg) aged 3 to 4 mo were randomly allocated to 3 treatment groups, including surgical castration, castration in combination with TA, and uncastrated controls. In Trial 1, pain-related behavior was assessed using a customized numerical rating scale (NRS) over 4 h. In Trial 2, pre- and postoperative skin sensitivity of the wound and periwound areas was assessed using an electronic von Frey anesthesiometer (IITC Life Sciences, Woodland Hills, CA) and von Frey monofilaments (300 g). Sampling was repeated at 1 min and 2, 4, 6, and 24 h after castration. Pain threshold was measured as maximum pressure (g) exerted by the electronic anesthesiometer to invoke animal reflex, and responses to the von Frey monofilaments were scored from 0 to 3 using a NRS on the basis of local and central motor reflexes. Calves treated with TA displayed significantly less pain-related behaviors up to 3.5 h after castration than untreated calves (P < 0.001) and did not differ from uncastrated controls. Topical anesthetic-treated calves also exhibited significantly greater pain threshold of the wound (559.2 ± 14.3 g) and surrounding skin (602.8 ± 16.5 g) than untreated calves (446.0 ± 18.9 and 515.3 ± 20.4 g, respectively; P < 0.001). Control and TA-treated calves had significantly lower mean response scores to von Frey stimulation than untreated calves (0.333, 0.978, and 4.289, respectively; P < 0.001). Results indicate that TA effects rapid and prolonged pain alleviation in calves up to 24 h after castration. Topical anesthesia may present a cost-effective, practical, on-farm approach to pain alleviation and is proposed as a potential tool for reducing the welfare impact on the beef animal in routine husbandry procedures.

Duration of action of a topical anaesthetic formulation for pain management of mulesing in sheep

OBJECTIVE

To investigate the effect of topical anaesthesia on 'mothering up' of lambs after mulesing and marking, and for pain alleviation over a 24-h period.

DESIGN

Two separate trials were performed on Merino lambs undergoing the mules procedure for flystrike prevention, to assess the efficacy of immediate postoperative topical anaesthetic wound dressing containing lignocaine (hydrochloride) 40.6 g/L, bupivacaine (hydrochloride) 4.5 g/L, adrenaline (tartrate) 24.8 mg/L and cetrimide 5.0 g/L in a gel base (Bayer Animal Health, Gordon, NSW, Australia).

METHODS

In both trials, lambs were assigned to one of three treatment regimens: control, mules procedure with topical anaesthetic (0.5 mL/kg) and mules procedure without topical anaesthetic treatment. Parameters measured included body weight, assessment of skin and wound sensitivity to light touch and pain stimulation, behavioural responses and time to mother up and to feed.

RESULTS

In both trials there was rapid (1 min) and prolonged (up to 24 h) wound analgesia as shown by lower scores for light touch (P<0.001) and pain responses (P<0.001), with absent or significantly diminished primary and secondary hyperalgesia (P≤0.05) and significant reduction in pain-related behaviours (P<0.001) in treated versus untreated lambs.

CONCLUSION

Significant pain alleviation and improved recovery can be achieved in lambs for at least 24 h after mulesing through the use of topical anaesthesia. It is suggested that the haemostatic action of adrenalin, together with inhibition of the inflammatory cascade and the barrier effect of the gel within the product, may explain the prolonged anaesthesia up to 24 h observed in the present study. These results suggest that topical anaesthesia has the capacity to dramatically improve the welfare of lambs undergoing mulesing.

Brachygnathia, cardiomegaly and renal hypoplasia syndrome (BCRHS) in Merino sheep maps to a 1.1-megabase region on ovine chromosome OAR2

A genome scan was conducted to map the autosomal recessive lethal disorder brachygnathia, cardiomegaly and renal hypoplasia syndrome (BCRHS) in Poll Merino sheep. The scan involved 10 affected and 27 unaffected animals from a single Poll Merino/Merino sheep flock, which were genotyped with the Illumina Ovine SNP50 BeadChip. Association and homozygosity mapping analyses located the disorder in a region comprising 20 consecutive SNPs spanning 1.1 Mb towards the distal end of chromosome OAR2. All affected animals and none of the unaffected animals were homozygous for the associated haplotype in this region. These results provide the basis for identifying the causative mutation(s) and should enable the development of a DNA test to identify carriers in the Poll Merino sheep population. Understanding the molecular control of BCRHS may provide insight into the fundamental genetic control and regulation of the affected organ systems.

Using abattoir surveillance and producer surveys to investigate the prevalence and current preventative management of Caseous lymphadenitis in Merino flocks in Australia

The prevalence of Caseous lymphadenitis (CLA) in Australia was estimated to be 5.2% using 2009 abattoir surveillance data from all States supplied by Animal Health Australia involving 5029 lines comprising 1 339 463 sheep. This is a decrease from the 26% estimated in a similar study in 1995. There was a significant difference (P < 0.001) in CLA prevalence between all states except Tasmania and Victoria (P = 0.75) with prevalences of 12.8 and 12.9%, respectively. Western Australia recorded the lowest prevalence with 1.0%. The average CLA prevalence for New South Wales was 5.3% and within three surveyed Livestock Health and Pest Authority regions (Tablelands, Central North and Central West) was 2.9, 4.9 and 4.4%, respectively. The attitude of the majority of producers surveyed in these three Livestock Health and Pest Authority areas was that CLA was of little or no significance (75%) but were aware of the need for CLA control with ~68% using 6-in-1 vaccine, though only 39.9% as recommended. It appears that the prolonged use of CLA vaccination has been successful in reducing the prevalence of CLA across Australia and particularly in New South Wales. Further improvements in communication of information on preventative management practices associated with lice control, importance of using an approved vaccination program, plus increasing producers’ awareness of the importance of CLA control, are indicated.

Lethal genetic disorder in Poll Merino/Merino sheep in Australia

OBJECTIVES

Characterise a lethal genetic disorder in Poll Merino/Merino sheep

DESIGN

Pathological description of a new congenital multisystem disorder in a commercial sheep flock, and analysis of breeding data collected each lambing season between 2004 and mid-lambing season 2010.

PROCEDURE

Necropsies were conducted on six affected lambs and the mode of inheritance of the disorder was determined by pedigree and segregation analyses.

RESULTS

The affected lambs were dwarfs with multiple defects in several organs, including skeleton, heart, liver and kidneys. The disorder has been named brachygnathia, cardiomegaly and renal hypoplasia syndrome (BCRHS). Segregation analysis suggests the disorder is transmitted as an autosomal trait with a recessive mode of inheritance. An annual incidence of the disorder in the discovery flock of up to 2.5% was recorded.

CONCLUSIONS

As a lethal disorder, the occurrence of BCRHS raises potential ethical and economic concerns for Merino breeders. The development of a DNA test would be useful to investigate its distribution in the Australian wool-sheep population. As the disorder affects both the skeleton and several critical organs, including the heart, it may provide a potential animal model for investigating key developmental processes in humans and other animals.

Improvement in smallholder farmer knowledge of cattle production, health and biosecurity in Southern Cambodia between 2008 and 2010

Farmer knowledge surveys were conducted in 2008 and 2010 in Cambodia to evaluate the impact of a research project studying interventions that can improve cattle production and health, including biosecurity and practices relating to risks of transmission of transboundary diseases. The project hypothesis is that by increasing the value of smallholder-owned large ruminants through nutritional interventions and improved marketing, knowledge-based interventions including risk management for infectious diseases such as foot-and-mouth disease (FMD) can be implemented into a more sustainable pathway for rural development. Between 2008 and 2010, significant improvements in farmer knowledge and attitudes were recorded in three villages in three provinces of southern Cambodia. This was achieved through participatory 'applied field research', 'on the job' training plus 'formal' training programmes. No cases of FMD were recorded during the study period in the 'high-intervention' (HI) villages despite the common occurrence of the disease in a nearby 'low-intervention' and many other villages in the three provinces. Whilst it is likely that protection of these villages from FMD infection was from increasing the herd immunity by vaccination, it could also have been partly because of a decrease in risk behaviours by farmers as a result of their increasing knowledge of biosecurity. The research indicates that smallholder farmers are motivated by nutritional interventions that improve the value of their cattle 'bank' and offer better marketing opportunities. This provides a more receptive environment for introduction of disease risk management for infectious and other production limiting diseases, best implemented for smallholder farmers in Cambodia by intensive training programmes. In lieu of a widespread public awareness programme to deliver mass education of smallholder farmers in disease prevention and biosecurity, livestock development projects in South-East Asia should be encouraged to include training in disease risk management as an important intervention if the current momentum for trade in large ruminant livestock and large ruminant meat is to continue to progress and contribute to addressing global food security concerns.

Perspectives on Australian animal health aid projects in South-East Asia

Future food security poses many challenges and with increasing prosperity and demand for meat, the emerging but largely unregulated trade in livestock and their products from developing countries in South-East Asia and particularly the Mekong region, pose enormous risks of transboundary disease epidemics. However this is a challenge that should be met as substantial improvements in large ruminant production through appropriate knowledge-based interventions can potentially move the largely rural smallholder populations of Lao PDR and Cambodia from subsistence to a productivity focus, offering a new pathway for poverty alleviation. Large development projects have been implemented in the Mekong region to facilitate this process and research is needed to define problems, identify and test solutions, and then suggest the most appropriate delivery mechanisms for promulgating the interventions that are most sustainable. Animal health aid projects are needed to improve livestock productivity, minimize risk to trade and human health and enhance the capacities of countries where there are significant gaps in the provision of veterinary services. Improving large ruminant production, particularly through forages technology and infectious disease risk management including village-level biosecurity, provides a potential driver of foot and mouth disease (FMD) control and eventual eradication in the region. A perspective on issues involved in Australian aid projects addressing regional animal health research and development and a checklist of strategies to consider when designing and managing such projects is provided.

Topical anaesthesia alleviates short-term pain of castration and tail docking in lambs

OBJECTIVE

To investigate the effect of a topical anaesthetic formulation on pain alleviation, wound healing and systemic levels of local anaesthetic actives in lambs undergoing castration and tail docking.

DESIGN

Three placebo-controlled and/or randomised experiments were conducted using three groups of Merino lambs (n = 62, 68 and 19) undergoing routine castration and tail docking.

PROCEDURE

Surgical castration, with either surgical or hot-iron tail docking, was performed with and without the application of topical anaesthetic (Tri-Solfen) or placebo. The effects of this procedure were compared with those of rubber ring castration and tail docking, and of the handled but unmarked controls. Wound pain was assessed using calibrated Von-Frey monofilaments over a 4-h period, pain-related behaviour was assessed over 5 h, wound healing was assessed at 14 and 28 days, and the plasma levels of lignocaine and bupivacaine were determined.

RESULTS

Rapid and up to 4 h primary hyperalgesia developed following surgical castration and tail docking in the untreated and placebo-treated lambs. It was absent in the castration wounds, and significantly reduced in the tail-docking wounds, of the treated lambs. Hot-iron docking was associated with mild and transient secondary hyperalgesia, which was abolished by the topical anaesthesia. There was a significant reduction in pain-related behaviours in treated lambs, which were not significantly different in their behaviour to the sham-operation handled controls. Plasma lignocaine and bupivacaine levels were below the toxic thresholds in all tested lambs.

CONCLUSION

Topical anaesthesia alleviates wound pain and significantly reduces pain-related behaviours in lambs undergoing surgical castration plus surgical or hot-iron tail docking, without a negative effect on wound healing or a risk of systemic toxicity.

Financial modelling of the potential cost of ovine Johne's disease and the benefit of vaccinating sheep flocks in southern New South Wales

OBJECTIVE

To develop an enterprise gross margin (GM) model that predicts the on-farm financial impact of ovine Johne's disease (OJD) for various sheep enterprises in Australia. In addition, to estimate the benefits and costs of control through the use of the Gudair vaccination, including a breakeven point.

DESIGN AND POPULATION

Data for the model was gained from an observational study conducted over a 3-year period from 2002 to 2004 using sheep from 12 OJD-infected flocks from southern New South Wales. Flocks ranged between 3500 and 20,000 sheep, with owner estimates of 5% or greater OJD mortality at the start of the study.

PROCEDURE

A GM model was developed to predict the on-farm financial impact of OJD for various sheep enterprises in Australia, comparing non-infected, infected (status quo) and infected (vaccination) disease scenarios.

RESULTS

Vaccination breakeven points are achieved within 2 to 3 years for breeding enterprises if OJD mortalities are high, rising towards 7 years for a Merino ewe enterprise if OJD mortalities are low.

CONCLUSION

The GM model demonstrates the returns to investment of vaccination for Australian sheep producers with OJD-infected flocks.

Impact of topical anaesthesia on pain alleviation and wound healing in lambs after mulesing

OBJECTIVE

To investigate the impact of using the topical anaesthetic preparation Tri-Solfen on pain alleviation and wound healing in lambs undergoing mulesing.

DESIGN

Three separate trials, placebo controlled and/or randomised, were carried out over a 5 month period on three mobs of between 60 and 263 merino lambs undergoing routine mulesing.

PROCEDURE

Wound pain was assessed using 10 and 75 g calibrated Von-Frey monofilaments to determine sensitivity to light touch and pain stimulation over a 4 to 8 h period. Pain-related behaviour was documented by trained, blinded observers using a numerical rating scale. Wound healing rates were determined using scaled digital photography and image analysis software to calculate contraction in wound surface area 2 and 4 weeks after mulesing.

RESULTS

There was rapid (3 min) and prolonged (up to 8 h) wound analgesia as shown by pain response scores (P < or = 0.01), with absent or significantly diminished primary and secondary hyperalgesia (P < or = 0.01) and significant reduction in pain-related behaviour (P < 0.001) in treated versus untreated lambs. In addition there was improved wound healing in the treated lambs (P < or = 0.05).

CONCLUSION

Tri-Solfen effects rapid and prolonged wound analgesia, reduction in pain-related behaviour and improved wound healing in lambs undergoing routine mulesing, providing effective alleviation of pain associated with routine mulesing in sheep.

Lesions attributed to vaccination of sheep with Gudair for the control of ovine paratuberculosis: post farm economic impacts at slaughter

OBJECTIVE

To determine i) the prevalence of lesions at the site of vaccination with Gudair, and ii) the incidence of discounting of slaughtered sheep carcasses due to the presence of these lesions.

DESIGN

A survey of the prevalence of injection lesions and actual discounts applied to 20 consignments of vaccinates slaughtered in abattoirs in New South Wales.

PROCEDURE

Consignments of sheep previously vaccinated against ovine Johne's disease (OJD) were assessed on the slaughter chain for the prevalence of vaccination site lesions and any costs associated with carcass trimming were estimated. In addition a telephone survey was conducted to determine the experiences and risk attitudes of 8 abattoirs in south east New South Wales likely to have previously processed vaccinates.

RESULTS

The prevalence of lesions observed was 18% for adult (mutton) and 65% for lamb carcasses. The value of the trim removed was insignificant, the labour cost of its removal was nil and no carcass was downgraded to a lower value grade.

CONCLUSION

Under the market conditions existing at the time the study was conducted, in sheep vaccinated at the recommended site high on the neck, it is unlikely that OJD vaccination site lesions will be a significant cost to producers or the processing industry and will represent only a very small proportion of the total cost of OJD control by vaccination.

Lesions in sheep following administration of a vaccine of a Freund's complete adjuvant nature used in the control of ovine paratuberculosis

CASE HISTORIES

Occurrences of adverse reactions in seven sheep flocks in Australia following vaccination against paratuberculosis where veterinary attention was requested are reviewed. All cases occurred within the 3-year period following commencement of use of a vaccine of a Freund's complete adjuvant nature, at a time when approximately six million doses of vaccine had been administered.

CLINICAL FINDINGS

In the first case, 26/58 (45%) Merino sheep vaccinated as adults had palpable tissue reactions at or near the site of vaccination; enlarged prescapular lymph nodes were palpated in 17 (29%), and nine (16%) sheep had both palpable lesions at the site of vaccination and enlarged prescapular lymph nodes. The reactions included caseous nodules up to 5.5 cm in diameter. In the other cases, fistulating or granulomatous wounds were occasionally found at the recommended site of injection behind the ear, and myiasis was rare. Occurrences of inappropriate choice of injection site were recorded, including injection into the axilla of two Merino rams, and lesions in the tissues of the maxilla and nose of almost 50% of 350 Border Leicester lambs. Four outbreaks of progressive paralysis due to injection into cervical musculature were reported, described as "OJD staggers" by producers.

DIAGNOSIS

Granulomatous cellulitis and lymphadenitis associated with oil droplets typical of "oil granulomata". Injection of vaccine into the dorsal cervical area resulted in progressive paralysis due to myonecrosis and suspected granulomatous leptomeningitis. CLINICAL RELEVANCE AND CONCLUSIONS: Although lesions at and near the site of injection are common, adverse reactions to vaccination were rare and included mortality from cervical spinal injection, production losses from injection in the maxilla or axilla or if myiasis resulted, and potential marketing losses if animals or carcasses are discounted as a result of the lesions. Risk factors for adverse reactions included inadequate restraint of sheep, breed of sheep, experience of the operator, poor injection technique, and inappropriate placement of vaccine. Increasing attention to the proper restraint of animals, restricting vaccination to the recommended site behind the ear, careful placement of the vaccine into subcutaneous tissue to avoid drainage of vaccine material into tissues such as the spinal cord, and post-vaccination supervision to address welfare concerns should adverse reactions occur are recommended.

Losses of adult sheep due to ovine Johne's disease in 12 infected flocks over a 3-year period

OBJECTIVE

To measure the biological and financial impact of ovine Johne's disease (OJD) mortalities on 12 infected flocks within the endemic area of southern New South Wales over a 3-year period.

DESIGN AND POPULATION

An observational study was conducted over a 3-year period from 2002 to 2004 on sheep from 12 OJD-infected flocks from southern NSW. Flocks ranged from between 3,500 and 20,000 sheep. At the start of the study owner estimates of OJD mortality were 5% or greater.

METHOD

Annual mortality rates were estimated from farm records provided by owners. The proportion of OJD mortalities was assessed after histological examination of tissues collected from dead and moribund sheep during 5-day necropsy inspections conducted in autumn, winter, spring and summer in 2002. The financial impact was estimated using a gross margin analysis for each of the three study years and by placing a financial value on the necropsied sheep.

RESULTS

On the 12 farms, the average OJD mortality rate was 6.2% (range 2.1% to 17.5%) in 2002, 7.8% (range 1.8% to 14.6%) in 2003 and 6.4% (range 2% to 11.9%) in 2004. The average decrease in gross margin due to OJD infection on a farm in 2002 was 6.4% (range 2.2% to 15.4%), 8.5% (range 3.1% to 15.8%) in 2003 and 7.4% (range 1.5% to 15.4%) in 2004. This equates to an average reduction in annual income of $13,715 per farm per year. OJD losses accounted on average for two thirds of the total estimated financial loss associated with sheep deaths.

CONCLUSION

This study demonstrates the significant biological and financial impact of OJD on sheep flocks. These findings are of relevance to all Australian sheep flocks infected or at risk of OJD infection.